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Modeling of the Return Current in a Light-Addressable Potentiometric Sensor
Tatsuo Yoshinobu1,2, Daisuke Sato3, Yuanyuan Guo4
1Department of Biomedical Engineering, Tohoku University, 6-6, Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan. nov@ecei.tohoku.ac.jp.
Sensors (Basel, Switzerland)
|October 24, 2019
Summary
Minimizing circuit series resistance is crucial for light-addressable potentiometric sensors (LAPS). This study models return current to improve LAPS performance, signal-to-noise ratio, and spatial resolution.
Area of Science:
- * Semiconductor-based chemical sensing
- * Optoelectronic device physics
Background:
- * Light-addressable potentiometric sensors (LAPS) utilize photocurrent for analyte detection.
- * LAPS offer spatially resolved measurements via scanning light beams.
- * Signal loss due to return current impacts LAPS performance (SNR, resolution, sensitivity).
Purpose of the Study:
- * To propose a circuit model for understanding LAPS return current.
- * To investigate the influence of various parameters on return current.
- * To identify strategies for mitigating return current effects.
Main Methods:
- * Development of a circuit model for LAPS return current.
- * Analysis of parameter dependence (contact area, modulation frequency, conductivity, series resistance).
- * Comparison of model calculations with experimental data.
Main Results:
- * A circuit model for LAPS return current was successfully developed.
- * Return current is influenced by contact area, modulation frequency, solution conductivity, and series resistance.
- * Minimizing circuit series resistance is critical for optimal LAPS performance.
Conclusions:
- * The proposed circuit model accurately predicts LAPS return current behavior.
- * Minimizing series resistance is key to overcoming signal loss and enhancing sensor performance.
- * The study provides insights into LAPS limitations and optimization strategies.
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